Refrigerated beverage dispenser



Feb. 24, 1953 R, HULL 2,629,236

REFRIGERATED BEVERAGE DISPENSER Filed May 19, 1949 5 Sheets-Sheet FIGIINVENTOR. OB RT HULL HTTORME Feb. 24, 1953 R. R. HULL REFRIGERATEDBEVERAGE DISPENSER 5 Sheets-Sheet 2 Filed May 19, 1949 3 2 3 X f 3 XWO'EBFOQ 0000000000 ooooooo 0000000000 0% O0 88 O0 O0 2 so 00 O0 FIGZFIG.3

INVENTOR. ROBERT R. HU LL BY 9 TTOQNE Y 1953 R. R. HULL 2,629,236

REFRIGERATED BEVERAGE DISPENSER Filed May 19, 1949 5 Sheets-Sheet 5 lol2 FIGA 23 5 45 FIG. 5

22 CON I'ROL U ELEMENT INVENTOR.

ROBERT R. HULL 7? BY W R FIG. |o.. %HTTOWEY R. R. HULL 2,629,236

5 Sheets-Shayu 4 JNVENTOR. ROBERT R. HULL BY 6) fiQTTORNEY 5 6 m M mm F8 7 Z 3 M 5 B W O wM W M L Z r all I A a/ 1 M J 2 w AA 7/// A/REFRIGERATED BEVERAGE DISPENSER Feb. 24, 1953 Filed May 19, 1949 (03 I8' v-wi Feb. 24, 1953 R. R. HULL REFRIGERATED BEVERAGE DISPENSER 5Sheets-Sheet Filed May 19, 1949 FIG.7

FIGS

INVENTOR. R E T R. HULL j sulating ring, part in dotted lines; I

' 1 details of "construction; V

Patented Feb. 24, 1953 UNITEo STATE REFRIGERATED s PATENT OFFICE.

BEVERAGE DISPENSER l Robert R. Hull, Pasadena, Calif., assignor toSunkist Growers; Inc.,a corporation of California 1 Application May1911949, Serial N 94,171

My present invention relates to a sanitary 5 Claims. (Cl. 62-141)beverage dispenser of the mechanically refrig-' erated type, pleasing inappearance and capable of rapidly reducing the temperature of a beverageto a desired level and of maintaining it at that temperature level whilecontinuously gently agitating the beveragax I My inventionpcssessesthose outstanding, yet

always difilcultly attainable, attributes of utmost simplicityofconstruction and ease of operation. It comprises a refrigerated storageand U dispensing container in which thc container is v formed withplain, simple surfaces, preferably transparent for display purposes, iscompletely and instantly removable for cleaning or exchange 1. withoutdisengagingiany fastenings, has no auxiliary openings, connections,origadgets to permit provision of agitation or. thermostatic controLandyet provided witha'n efiicient agitator within the container andwithiasensitive and effectivethermostatic control.

My machine embodies a beverage container supported in contact witha'coldplatefor [the purpose of refrigerating thefbeverage, an outer shell"spaced) from and surrounding the beverage container to provideinsulating air space,

an agitator for the, beverage, and drive mechanism therefor. 'Ihe"drivemechanism includes a relatively stiff flexible link connecting arotating crank toan' oscillatingcrank and a safety clutch through whichthe oscillating crank drives the agitator. A temperature control bulb ismounted on the cold plate in contact with the beverageconteinerandinsulated from the cold plate in order to eiiectively c ontrolthebeverage temperature within relatively close limits. All

v of the foregoing mechanl'sm'is' neatly and compactly arrangedandcompletely housed so that the mechanism may not bejtampered withunless the machine is-partly disassembled In thedrawings':

bracket, and switch assembly taken substantially hub shown in section; w

Figure 9 is an elevation of my agitator drive shaft bracket and switchassembly, the switch operating and stop screws being omitted :for thesake of clarity; and t Figure 10 is a schematic wiring diagram of mydevice.

It is known that many beverages are more palatable when served coldand'that some beverages retaintheir palatability as well as otherdesirable and important characteristics for a longer period of time whenmaintained at a relatively low temperature; This is particularly true ofcitrus juices such example.

In order to cool a beverage and keep it cool, it is important tofacilitate heat transfer from the beverage to the cold plate of therefrigerating unit on which the beverage container is supported. Toaccomplish this satisfactorily, and to assure efiicient and sensitiveoperation of the temperature control unit, it is desirable to keep asfresh orange juice, for

. the beverage constantly in motion. This is ab- Figure 1 is aperspective viewof my dispenser showing the gener'alj arrangement andoutward appearance thereof Figure 2 is a side yiewo f my dispenser,partly "in "section to better show some of the structural details; i i

complished in my device by means of a continuously operated, oscillatingagitator which also serves to maintain insoluble solids uniformlydistributed throughout the beverage. Such solids arelpresentin' freshorange juice, for enample, which contains a pulpy material mostly in theform of ruptured juice cells or sacs. These cells or sacs impart adesirable characteristic flavor to the juice, but, unless a gentleagitation or stirring action is constantly maintained, they will eithersettle to the bottom or float to the top of the beverage, resulting in alack of uniformity of solids in the individual portions of beveragedispensed from time to time. Unless adequate "agitation is provided, iceis likely to be formed Figure 3' is a pa'rtialsectional view of mytermperati ire control bulb and its associated heat inorthe cold platebeing shown Figure 4 is arearelevation of my dispenser,

the basecasing being insection an d the outer shell, beverage-container,and part -ofthe supon the inside of the container. The formation of suchice may prevent the control from functioning properly in response tovariations in beverage temperature. 1

My dispenser comprises a base It! having a superstructure ll supportedthereon As shown in Fig. 4, and more particularly in Fig. 7, the base"port bracket-bemg-omitted to better show certain houses a compressorunit l2 containing a builtinmotor and a compressor driven thereby, a mo-'3 or i g fan- 14 and agitator snare l5,

a refrigerant condenser l6, and other control elements and mechanismsassociated with the motors and the refrigerating system. A cold plate 2|made of stainless steel or other suitable material forms a top for thebase.

The superstructure, as shown in Figs. 1 and 2,

' includes a beveragecontainer 25 and outer shell 24 having a cover 26.I prefer to make the container and shell or transparent material such asa transparent plastic but other transparent, translucent, or opaquematerial may be used if desired.

The perimeter of the cold-plate 2| is provided with a depressed portionor trough 'Zla which receives the lower portion of outer shell 24 andalso the lower portion 25b of beverage container 25. The troughcooperates with the shell and the container to facilitate their accurateplacemerit in a centered, concentric position and prevents lateraldisplacement from this position. The trough also serves to retain anymoisture that may be present due to condensation, for example.

A cover 26 is provided for the outer shell 24 and g may be securedthereto by means of suitable bolts 39. A small door Zlis hinged to thecover'at 23 and may be provided with a knob 29.

An internally threaded boss 32 is secured to the beverage container 25adjacent the bottom thereof for the reception of spigot 3!. Outer shell24 is provided with a cutaway portion 33 through which the stem ofspigot 31 extends. This cutaway portion permits removal of the outershell by merely lifting the same out of the trough Zia. The bottom 25aof the container 25 is preferably made much thinner than the containerwalls. This relatively thin bottom will 'conform't'o any slightirregularities of the surface of the cold plate 2! so that a relativelycomplete contact is had between these elements to facilitate the flow ofheat from the beverage in the container to the cold plate. The thinbottom will, in addition, have considerably less resistanceto the flowof heat than would a thicker bottom. A side wall extension 2527 issecured to the bottom of the container. This may take the form of a ringcemented or otherwise securedto the container bottom at its outerperiphery. One of the functions of this ring is to cooperate'with thecold plate 31 may be removed from the trough for the purpose of cleaningthese elements.

The refrigerant, which may be Freon No. 12 (dichlorodifluoromethane) orother suitable material, normally flows as gas from the high pressureside of the compressor unit l2, Fig. 7, through tubing I I to thecondenser [Efrem which it flows as liquid through tubing I 8 preferablyto the center of refrigerating coil I9, Fig. 2, which in turn dischargesthrough tubing I81; to the low pressure side of the compressor unit. Thecondenser is curved, as shown in Fig. 7, in order to facilitate acompact arrangement of the various components in the base. The condensermay be made inyarious ways but I have found it expeclient to make itflat and then bend it to the desired curvature. I prefer to deliver theliquid refrigerant to the center of the coil 19 so that it will flowoutwardly to .theperiphery This arrangement makes it possible to sodesign the refrigerating mechanism and to adjust the refrigerant chargeas to maintain the outer area of the periphery of the cold platewhich isnot covered by the beverage container relatively warm and thus minimizeor prevent the formation of frost or condensate on this area. Frostingof the outer periphery of the cold plate covered by the container bottomis also prevented or reduced, thus preventing or reducing the stickingof the container to the cold plate duetofrost A dehydrating element 20,Fig. S4 is interposed in line I8 to remove any trace of Water that maybe present in the refrigerant. A

Refrigerating coil I9 is 'solderedor otherwise secured to cold plate Hin any suitable manner that will facilitate the exchange of heat betweenthese elements. This coil preferably covers a substantial area of thecold plate, leaving, a free portion in whicha thermostat control bulb 22and its heat insulating ,ring 90 [are positioned. As shown, therefrigerating element or coil I9 is annularin arrangement for convenienc e of manufacture, and the free portionis at the center. While I haveshown and prefer to use a coil as the refrigeratin'gelement, thiselement may be formed in other shapesor forms if desired. My

7 cold plate is shown as circular in the drawings trough '2 la tolocateand maintain the container tainer bottom 25a out of contact withany fiat supporting surfaceupon which the container may be placed whenremoved from the machine. Ihis prevents the container bottom frombecoming ;scratched and from picking up dirt 'or other foreign materialwhen-removed temporarily from the machine. Such dirt or other matterwould,

7 unless removed, preventa good heat conducting contact between thecontainer bottom and the cold plate and would greatly impair theefficiency of the cooling mechanism.

A base casing 36 of stainless steel or other suitable materia1 surroundsthe base and encloses the mechanism located therein. Drip trough 35isdetachably secured to the casing 35 below the spigot 3 I and isprovided with a removable grating 31 on whicha cup or other receptaclemay be placed, in beverage receiving position, during.

the dispensing'operation, Drip trough 35 may be readily detached fromcasing 36; and gratin but it may be rectangular or of any other shapedesired. It is preferable in all cases, however, to supply therefrigerant to. the element in such a manner that the flow will beoutwardly toward the periphery of the cold plate for the reasons setforth above.

I now wish to callattention in detail to a further important aspect ofmy invention.-

In use, dispensers of the type disclosed may sometimes be filled withbeverage at a temperature higher than the temperature at which thebeverage is to be maintained in the dispenser. The temperature of thisbeverage may in some instances equal or exceed normal room temperature,Whereas it may be desirable to dispense the beverage at a lowertemperature, In thecase of orange juice, for example, a highly desirabletemperature at which to maintain the juice in the dispenser isfrorn 32F. to about 34 F. It is, therefore, desirable to use the full capacityof the refrigerating mechanism by running it continuously from the timethe beverage at relatively high temperature is placed therein until itisreduced to thetemperature whereit is to be maintained withinrelativelyclcseliniits. g

If the controi bulb of ,a conventional bellows type temperaturecontrolunit is placed in the beverage container, operation of therefrigerating A mechanism controlled a eca'cso by that unit'will bedependent upon the temperature of the beverage. If the beverage isconstantly agitated, operation will be satisfactory without iceformation provided the control is properly adjusted. Such anarrangement, however, introduces sanitary and mechanical diflicultiesthat have, insofar as applicant is aware, ruled out the use of thiscontrol arrangement in applications where sanitary conditions must bemaintained. Maintenance of sanitary conditions is, of course, a primerequisite in a device ofthis general class. In a dispenser of the typeherein disclosed the container must the cold plate or with therefrigerating'coih'for the beverage actually to get warmer rather thandirectly in contact with the cold plate or the w refrigerating coil doesnot result in operation of therefore be removed frequently for cleaningand sterilizing. This would involve lifting the control bulb out of thecontainer, during which operation the capillary tube connecting it tothe bellows would be flexed and subject to breakage. The control bulband capillary tube could not readily be cleaned or sterilized. For thisreason they would notmeet the health requirementsof most localities. ofthe gas from the bulb or capillarytube into the beverage and thispossibility is even more a likely where an agitator is employed,inasmuch There is also a possibility of leakage as it might rupture thebulb or capillary tubeif it should come in contact therewith. ,It willbe seen, therefore, that it is desirable .to locate the control bulb atsome point other than within the,

beverage container.

The bulb could be located directly in contact with the cold plate orwith its refrigerating coil. When so located it would have to be soadjusted as to stop the refrigerating mechanism before the cold platereached atemperaturelow enough to result in the formation ofice in thebeverage whenever the temperature of the beverage should approach itsfreezing point. Otherwise, ice would i always be expected to formeventually. This control could,.therefore, only be set at a temperatureslightly below the freezing point of the beverage and itwould have to beset to cut off the. refrigcrating mechanism at this temperature. Withsuch a control, the refrigerating mechanism would start to run whenbeverage at room temperature,

or at any temperature substantially higher than that for which thecontrol was set, was placed in the container, but it would not continueto run until the whole body of the beverage was reduced tothe controlpoint, say, approximately 32 F. It would run only until therefrigeratingcoil or cold plate, not the beveragawas. reduced to that temperature. Itis manifest, therefore, that the operation of the refrigeratingmechanism would 1 be initially cut off before the beverage was re ducedto the desired temperature. The beverage, after the first cut off of therefrigerating mechanism,.would still be relatively warmandwouldtherefore rather quickly rewarm the control bulb,

thus causing the refrigerating mechanism to start to run again: Theabove cycle would then be repeated. Moreover, it would continue, toberepeated, and at increasing. frequency. as the beverage temperaturedecreased, since less. time would be required in each instance to coolthe control bulb back down tothe temperature consponding to themaximumcapacity of therefrigcrating mechanism. It is evenpossible, whenthe control bulb is located directly in contact with the refrigeratingmechanism in direct response to the beverage temperature, but rather inresponse to the temperature of the refrigerating coil or cold plate.With such'a control arrangement,

' the full capacity of the refrigerating mechanism cannot be utilized toquickly reduce the beverage temperature to the desired dispensingtempera- Obviously, however, great advantages are to be achieved in easeand low cost of manufacture, in convenience in installing and removingthebeverage container, and in cleansing and caring for both the beveragecontainer itself and forthe rest of the machine, if, while at thesametime achieving both effective temperature control within thebeverage and maximum effective utilization of the capacity of therefrigerating mechanism, it is possible simply to set the .containerupon the cold plate to install it and to pick it up againto remove it,with no connectionor fasteningto be inserted or removed or to beadjusted.

I have succeeded both in overcoming the difii- .culties explained aboveand in achieving the above stated highly desirable results, all of whichI accomplish by mounting my temperature control bulb 22 integrally, withthe cold plate 2! and within the area of the surface thereof and at thesame time surrounding the control element 22 with heat insulating ring90. This assemblage is shown in detail in Fig. 3. This insulating ringis preferably made of materal that is impervious to moisture, a poorheat conductor, and readily machinable or capable of being otherwisereadily fabricated. I have found in practice that paper base phenoliclaminated fibre is a suitable material and this is the one I prefer touse. The in sulating ring is preferablycircular as shown in Figure 1 andis provided with a central opening 9|, counterboredat 92 to receive thecontrol bulb 22. Thecontrol. bulb may be made of stainless steel orother suitable material and is provided witha rim 93 which is receivedin the counterbore .access to the control bulb system for charging withanysuitable gas, such as methyl chloride,

for example. After charging, tube 96 is pinched off and is solderedo'r'otherwise sealed to close the. system. Suitable openings 81 areprovided for the purpose of receiv'ing'bolts tea which are welded orotherwise secured to the bottom of the cold plate and which serve .tosecurering tie and its-associated:control'bulb 22 in centrally locatedopening 98 in the complete. Ksui'table cement is also applied to thecold plate, bulb, and ring 7 plate and. torestrict the flow of heattherefrom to the cold plate, I reduce the cross sectional area of thering 90 by forming an annular groove 9 9 therein, concentric with andsurrounding the opening 9i. Capillary tube 94 communicates with thebellows of a control element Ill-I, Fig. 4. Any high quality controlhaving a narrow range of response may be used. The control includes aswitch operated by the bellows in response to variations .in pressure inthe system resulting from variations in temperature of the control bulband the gas contained therein. 1 connect this switch in my compressormotor circuit so that operation of the compressor is governed by thecontrol.

It will, upon due consideration, be apparent that by the aboveconstruction and arrangement of elements, I have provided a system inwhich, during normal operation, the flow of heat will always be from thebeverage to the cold plate, inasmuch as the cold plate temperature willbe less than the beverage temperature. Assuming uniform resistance toheat flow over the bottom area of the container, the greatest flow ofheat will take place at t'he points or areas of greatest temperaturedifferential. This area of greatest temperature differential will be theannular area directly over the refrigerating coil. Heat flowing from thebeverage to the control bulb will, of course, tend to increase thetemperature of the bulb to a temperature approximating, but stillsomewhat below, the beverage temperature. In view of the fact that thecontrol bulb is insulated, as by means of ring 90, from the cold plate,there will be a minimum of heatflow through this ring from the controlbulb to the cold plate; and the temperature of the control bulb willconsequently vary substantially as the temperature of the beveragerather than as the temperature of the cold plate. 7

With this arrangement and in a commercial machine constructed inaccordance with the instant disclosure, it has been shown to be possiblefor the cold plate to reach temperatures in the neighborhood of F., orbelow but, inasmuch as the control bulb is responsive to beveragetemperature, the refrigerating mechanism will con tinue to operate untilthe beverage temperature reaches the desired point, at which time thecontrol bulb will have become cold enough to fimction to operate thecontrol mechanism and to shut off the refrigerating mechanism. It willbe seen, therefore, that when relatively warm beverage is placed in thecontainer a large temperature differential may be established andmaintained between it and the cold-plate, thus effecting a rapidreduction in the beverage temperature. Such a temperature differentialcould not be established or maintained if the control bulb were securedto the cold plateor to the refrigerating coil and directly controlled bythe temperature thereof, as pointed out heretofore.

It has been pointed out heretofore that the container bottom a, isrelatively thin and flexible so that it may conform to minorirregularities in the surface of the cold plate. In order to assure agood, heat conducting contact between the control bulb 22 and thecontainer bottom, I' prefer to crown the control bulb and insulatingring slightly so that the center of the control bulb is severalthousandths of an inch higher than the general plane of the cold platetail in Fig. 7, shaft 38 extends from one end of '3 motor I3 and drivesa fan I 4 secured thereto. The other end of "the motor is provided withareduction gear 39 which may be integral with the end bell of the motor.This has a vertical shaft 40 extendingtherefrom and rotating at a speedslower than that of motor I3. Crank M is secured to and supported by theend of shaft 40 and is coupled, by means of a connecting link 23, to acrank 42, having 'a greater throw than crank 4I, mounted on the lowerend of agitator shaft I5. The link 23 is made of nonstretchable,

noncompressible, flexible material such as relatively thin spring steelof sufficient stiffness and rigidityto transmit the desired thrust butsufiiciently 'fleiirible to bend or flex somewhat to compensate for anymisalignment of shafts I5 and 3B and to reduce the transmission ofvibrations. The term relatively stiff flexible as used hereinafterrefers to material having the foregoing characteristics. This linkconstruction also makes it possible to resiliently mount the motor I3and greatly reduces the transmission of vibration from this motor toother parts of the machine, thus reducing noise. It also greatlyfacilitates manufacture and assembly of the device, inasmuch as iteliminates the necessity of maintaining close'alignment tolerances ofthe shafts Ii and it and the cranks or other elements associatedtherewith as would be required with a rigid, :nonflexible link. The link23 is riveted, as by means of rivets 8B, or otherwise secured to blocksit and 235 at its respective ends These blocks are, conveniently, Lshaped and house bearings es preferably of the sealed and lifetimelubricated ball type, which receive the pintles 46 and 4'! on the cranks4i and 42 respectively. The bearings are a press fit in bores formed inthe blocks and are further retained in place by deforming the edges ofthese bores. Inasmuch as crank GI has a shorter throw than crank Q2,rotation of the former will result in oscillation of the latter throughlink 23.

As shown in detail in Figs. 6 and 9, crank 62 is ,iournaled on athreaded collar 53 which drives agitator shaft I5 through a safetyclutch arrangement including pin 48, the rounded end of which is urgedby spring 49 into a recess 58 in collar 53 secured to the lower end ofshaft IS. The size of the pin, the radius of the rounded end thereof,the strength of the spring, and the depth of the recess are such thatthis connection may transmit sufficient power to operate agitator shaftI5 when a normal load is imposed on the agitator 5 I, as during normaloperation. If for any reason agitator 5| is restrained from movement, asby the formation of ice in the container or during removal of theagitator, pin 48 will ride out of recess 56, thus preventing damage tothe restrained agitator, to the driving motor I 3, or to any of theintermediate connecting elements. A similar safety clutch arrangement isdisclosed and claimed in my copending application for Liquid Measuringand Dispensing Device, Serial No. 24,963, filed May 4, 1948', now U. S.Patent No. 2,570,681, granted October 9, 1951.

The agitator drive shaft I5 is ordinarily made tubular and is journaledin a vertical support or post 52 mounted on the base, centrally oftrough 2Ia. and between the outer shell 24 and the beverage container25. Bearings 54 and 55, preferably of the porous oil retaining type, areprovided for shaft I5 within post 52. An agitator drive hub 56 issecured to shaft I5 adjacent the upper end of bearing 54 by means of asetscrew 51 and is provided with an upwardly extending 9. key 58. Thelower end of drive shaft I is threaded at 59 to receive threaded drivecollar 53 which is held thereon by lock washer 60 and lock nut 6|. Nut62, threaded on the extreme lower end of the shaft I5, is provided withan opening 53 larger than the diameter of and through which one end of aswitch rod 64 extends. Rod 5t also extends axially through thedriveshaft. Cap 65 secured to the upper end of rod 64 is provided with adownwardly extending skirt 65 which surrounds a reduced portion 61 ofthe upper end of drive shaft l5. This arrangement provides a seal forpreventing the entry of water or other foreign substances to theinterior of drive shaft l5." The lower end of rod 64 is threaded-atta toreceive a nut 69,. which may be of the self loc'king type.

Spring I, which surrounds the lower end of rod 64 and bears against ashoulder) formed thereon, rests upon nut 62, thereby urging therodassembly upwardly. The strength of this spring is such that it will becompressed by the weight of the agitator-5i oncap- 65 yetit is madestrong enough to compresstheswitch springand over come friction. Q

"Iheentire agitator drive shaftassembly 12 extends throughanopening-Mina support bracket is and is secured thereto; as by welding orsoldering. The bracket 14 has a downwardlyextending portion 15 securedthereto and a-hori'zontally extending portionxlfi. This latterhorizontalpor tion supports a switch Tl which is normally closed butmaybe openedbypressure on its operating button '18. Button 'I8-is spring urged to aprotrudingposition bya spring (not shown) built into the switch and notconstituting a part of this inventioni I prefer to employ this switch Has a line switchyin which event itis connected in series with the lineand all electrical elements in my dispenser, as shown in Figure 10. Aswitch operating lever l9ispivoted at 80 to an angular brackethaving avertical portion 86 and a horizontal portion 81 and is provided with anopening 8| adjacent one end, through which the lower end of rod 64extends. The diameter of opening 8l,j like the opening63in'nut 62, islarger than the diameter of the lower end of rodM so that it does notcontact these openings when the machinery is runnin'g a'ndwearat thesepoints is consequentlyavoided. "Two screws 82 and 83 extend throughthreaded openings: adjacent the of such length that thevertical portionIDS is other end of lever l9'and are provided with lock nuts 84 and 85for locking them in adjusted. position. Switch operating screw 82 islocated directly above and operates switch button 18, whereas stopscrewtlilconstitutes an adjustable stop for limiting theclockwise'rotation of lever 19 about its pivot. l i

. In Figure 6 line switch" is shown in its closed position, rod 54 beingshown in its lower or depressed positionf This isthe position it assumeswhenthe agitatorf5l is in place to depressrod 54 against the tension of'spring H through contact with capli5. Whenthe agitator isremoved or whenit is liftedor'pushedup {for any reason so that its weightnolonger'holds rod 64 in its lower position, spring II will consequentlyurge. rod .54 to an upper position inwhich 'lever 19, through contactwith nut 69, will-be rocked clockwise about pivot 80 untiltheloWerendJof screw83 contacts the horizontal portion 8101? the angularbracket. In this position setscrew 82 wil1 have. depressed switch button'18, against the tensionof its builtin spring, sufliciently to open lineswitchll, thus interrupting the flow of current to all electricaldevices connected in 1 series therewith. q...

aeeegeso Nut 69 on the lower end of rod 64 is adjusted to clear lever 19when rod is in its depressed position, thereby eliminating frictionalcontact and wear between the nut and lever during normal operation ofthe dispenser. This nut may be of a self locking type so that it willremain in the position to which it is adjusted. Screw 82 is adjusted toa position where it will depress push button 78 sufficiently to operateswitch 11 when rod 64 moves to its elevated position and lever la isrocked clockwise about pivot 80 by nut 69. Set screw 83 is adjusted toprevent clockwise rotation of lever 19 substantially beyond a positionnecessary for the operation of switch ll. When all the foregoingadjustments are properlymade, thelower end of rod 54 and nut 89 willclear lever 19 and will not contact any part thereof during normaloperation of the machine with the agitator in position.

As shown in Figure 8, my agitator 5! is sub-' stantially Z-shaped and isprovided witha hub I62 having a cylindrical bore I93, to receive driveshaft l5, and a keyway I64. The keyway I04 receives the key58 to insurea positive but readily separable' driving connection between the hub andthe drive shaft l5. The inner end. of the bore I05 holds cap '65downagainst the tension of spring ll when the agitator is assembled on the'drive shaft. otherwiseseoured to the hub at I05.

In order'to obtain thorough but gentle agitation ofthe beverage I preferto make my agitator substantially Z-shaped with an upper horizontallegor portion I01 extending inwardly over and closely adjacent the topof container 25, as shownin Figure 2, and a vertically downwardlyextend-- ing portion I08. ,At a point I09 the agitator is bent towardits axis toform outwardly and downwardly sloped portion no which isagain bent at Ill toforinthe lower leg H2 of the 2 extendinghorizontally away from the axis of the drive shaft. i

The over-all dimensions of the agitator are suchthat its upperhorizontal leg I01 just clears the upper edge of beverage container 25and is approximately half way between the vertical axis ofthe beveragecontainer and the wall thereof. The over-allheight of the agitator issuch that the lower horizontalleg H2 just clears the container bottomand is preferably of a length equal to about three-fourths the-diameterof the beverage container.

Upon oscillation of my agitator about its drive consequently. swingthrough a greater are than point HI and will thus provide adequate agitation in. the upper portionof the container. Inasmuch as portion I lllissloped, any point thereon will swing through a greater or lesser arcthan any other point, the greatest arc being traversed by point I09 andthe smallest by point Thea'gitator is soldered or 1 casing-36 to admitair to the" tunnel. The air isthen forced by fan I4 through condenser I6and out to the atmosphere through vent openings H5 in the opposite sideof base casing 36. This. arrangement air-cools condenser I6 and providesventilation for the mechanism in the base assembly.

Cold plate 2I is supported on one or more annula'r rings I lfi'belowwhich a disk I I1 is secured. This arrangement provides a, space II8 below the coldplate which is filled with a suitable insulatingmaterial such as Santocel. This assembly forms a heat insulatingbulkhead between the mechanism in the base and the cold plate. Anopening H9 is provided in the disc to provide a passage therethroug'hfor the capillary tube 94 and the inlet and outlet tubing for coil I9,all of which connect to their respective associated elements within. thebase. The bulkhead assembly is supported on base I20 by means of aplurality of posts I2I spaced about the circumference thereof. Disk I I!also serves as a support for bracket 14, which is bolted thereto, andfor motor I3, which is supported thereon by suitable mounts I22. Iprefer to use rubber mounts in shear. in order to absorb motorvibration.

In servicing the machine, the door 21 may be opened and the beveragepoured therethrough into the container 25. If desired, the outer shell24 may be lifted 01f, thereby exposing the container 25 for filling. Inorder to remove the beverage container, the outer shell 24 is firstlifted'oif the base ID, the agitator 5| is then lifted off the driveshaft I5 and drive hub 56, whereupon line switch ll will open,disconnecting the electrical elements from the power line. The beveragecontainer may then be lifted 011? for emptying or cleaning. The beveragecontainer cannot be removed from the dispenser without removing theagitator and consequently shutting off the motors driving themechanisms. The refrigerating unit therefore ceases to operate while thebeverage container is removed and the build-up of an undesirable frostlayer on the cold plate, while the container is removed, is avoided.

, tsometimes happens that in servicing a machine ,of this-kind theoperator will remove the container for cleaning and then, for one reasonor another, not return the container to the cold plate for a relativelylong period of time. If a manually operated switch were relied upon andthe operator failed to turn the machine off when he removed thecontainer, a layer of frost would build upra'ther rapidly on the coldplate. This frost, unless removed, wouldform an insulating barrierbetween the bottom of the beverage container and the cold plate when itwas finally replaced. When the frost melted an undesirable accumulationof moisture would result. This frost build-up might in some instances besufficient to space the beverage container from the cold plate to suchan extent that the agitator would not clear the bottom of the containerand could not operate.

If for any reason, such as failure of the thermostat to operate, iceshould form on the bottom of the beverage container, the lower leg ofthe agitator will contact the ice and, inasmuch as'this leg isorbiculate in cross section, its motion with respect to the ice willcause the agitator to cam itself upwardly, whereupon line switch" willopen to disconnect all motors from thelirie'. Should the agitator failto cam upfor any reason, damage to it, to the container,

or to any of the driving mechanism is prevented.

by the slipping. of the drivingconection between crank 42 and collar 53occasioned by pin 48 riding out of recess 50.

While I have described certain features of my invention more or lessspecifically it will be evi-. dent to those skilled in the art thatvariouschanges and modifications may be resorted to. within the scope ofthe appended claims without departing from the spirit or scope thereon Iclaim: 7

1. Agitator drive mechanism for a beverage dispenserincluding anagitator support, a drive shaft journalled in said'support and adaptedto receive an agitator on its upper end, an electric motor foroscillating said drive shaft, a vertical rod extending through saiddrive shaft, a switch operable by said rod for controlling said motor,means for urging said rod upwardly to open said switch, and meansassociated with said agitator for preventing upward movement of the rodwhen the agitator is in its normal position, said switch closing thecircuit to said motor when the agitator is in said normal position andopening said motor circuit when the agitator is out of said normalposition.

2. A beverage dispenser including an agitator,"

a refrigerating system, electrically. operated mechanisms for drivingsaid agitator and said refrigerating system, and a line switch operablewhen said agitator is in normal position to close the power circuit tosaid electrically operated mechanisms and operable when said agitator ismoved to an abnormal position to open the circult and interrupt thepower supply to said electrically operated mechanisms, said agitatorbeing substantially Z-shaped and having a substantially horizontal lowerleg closely adjacent the bottom of a beverage container for oscillationin a plane parallel thereto, said lower leg of said agitator beingorbiculate in cross section so that in the event ice is formed in thebottom of the container the agitator may cam itself upwardly throughcontact therewith, whereupon the line switch may operate to interruptthe power supply.

3. In a beverage dispenser having a beverage container, a substantiallyZ-shaped agitator, the lower leg of said Z being positioned closelyadjacent the bottom of the beverage container for oscillation in a planesubstantially parallel to the bottom thereof, the upper leg of saidagitator being substantially shorter than said lower leg, said upper leghaving its free end pivoted about a perpendicular axis substantiallyoutwardly offset from the lower angle of the 2, said lower leg beingorbiculate in cross section so that it will cam itself upwardly throughcontact with any ice that may form on the container bottom, drivemeansfor the agitator including-a motor, a switch for said motor associatedwith the agitator and operable on upward movement of the latter tooperate the switch and disconnect the motor thereby disabling saidagitator drive means.

4. A beverage dispenser having a base, a beverage container supported onsaid base, an outer shell'of greater height than said containersupported on said base spaced from and surrounding the container, acover resting'on said outer shell. an agitator support extendingupwardly from said base between said container and said outer shell, anagitator drive shaft journaled-in said support for "oscillating anagitator mounted on the upper end thereof, ian'malectricswitch forcontrolling an agitator drive motor held in closed position by theagitator in its normal operating position, said agitator extending overthe upper edge of and depending into said container and havin a lowerleg adjacent the container bottom whereby an appreciable ice formationon the bottom will cam the agitator to an abnormal position and theswitch to open position to render said drive motor inoperative.

5. A beverage dispenser having a beverage container and an attenuatedagitator, the lower leg of said agitator being positioned closelyadjacent the bottom of the beverage container for oscillation in a planesubstantially parallel to the bottom thereof, said lower leg beingorbiculate in cross section so that it will cam itself upwardly throughcontact with any ice that may form on the container bottom, drive meansfor the agitator, an electric motor for operating said drive means, anda switch operated by the agitator and operable on downward movementthereof to energize and on upward movement to deenergize said electricmotor.

ROBERT R. HULL.

REFERENCES CITED The following references are of record in the file ofthis patent:

Number Number 14 UNITED STATES PATENTS Name Date Campbell et a1 Sept.24, 1872 Strowger July 17, 1906 Clark Aug. 23, 1921 Parker Dec. 7, 1926Altorfer Dec. 24, 1929 Fairgrieve Feb. 28, 1933 Edwards Apr. 10, 1934Frenning Oct. 16, 1934 Steenstrup Dec. 18, 1934 Killen Mar. 23, 1937Schaefer Oct. 19, 1937 Richards Nov, 25, 1941 Sticelber Dec. 9, 1941French June 23, 1942 Amador Jan. 3, 1950 Rabjohn Apr. 4, 1950 FOREIGNPATENTS Country Date Great Britain Nov. 27, 1919 Great Britain Aug. 3,1948

